We propose to purchase an ultra high resolution mass spectrometer for the determination of exact mass spectra up to 12,000 amu. The instrument will be available on a continuous basis for the acquisition of EI, CI, FAB and DCI spectra and thereby for the characterization of organic and bio-organic molecules. The proposed instrument will be available as a departmental service. The instrument will provide very dramatically improved mass spectra at both higher molecular weights and higher spectral resolution than our existing instrumentation. The primary user groups are carrying out research on the total synthesis of biologically active natural products, drug metabolism, polynucleotides, nitrosamines and pancreatic carcinogenesis and on the mechanisms of enzyme inhibition.